Where have the sea turtles gone?

Fri, 26 Apr 2013

“Sea turtles don’t come to nest on our beach anymore!” said Mr. Minh, a member of Sea Turtle Nesting Beach Protection, a volunteer network in Quang Tri Province. Despite the participation of nearly 3,500 local residents and school children in beach protection, a recent survey found that, since 2007, no marine turtle nests have been recorded in Quang Tri, Quang Nam, and Quang Ngai Provinces and the very few nests that remain in Binh Dinh Province are on off-shore islands. Meanwhile, according to a 2009 report by the World Wide Fund for Nature (WWF), 1,000 mature turtles a year are killed accidentally by fishermen as “by-catch”.

Four species of marine turtle are thought to nest along Vietnam’s central coast: the Green turtle, Chenolia mydas; Hawksbill, Eretmochelys imbricate; Olive Ridley, Lepidochelys olivacea, and Leatherback, Dermochelys coriacea. However, a 2012 helicopter survey along 500 km of coastline from Quang Tri to Binh Dinh failed to detect any nesting sites, despite near perfect conditions at the height of nesting season.

The airborne survey showed that shrimp farms, which were present along most of the beaches, was the largest threat to turtle nesting habitats (Figures 1-3). The scale of these farms ranges from small family owned plots to large-scale industrial enterprises. The noise, lighting, and pollution associated with the shrimp ponds both deter the turtles from nesting and destroy nesting habitats.

Shrimp farming on sandy beaches started in Ninh Thuan in 2000 and has expanded rapidly north, all the way to Ha Tinh. As they move north they leave behind a highly polluted environment that not only destroys turtle nesting habitat but ruins any prospects for tourism. Despite the damage, the businesses are never required to restore the beaches; the simply move on to new beaches, usually after a few years when the ponds become polluted. In economic terms, the shrimp industry is not required to pay for the “negative externalities” it generates.

As Lang Co shows, Central Vietnam is home to some of the world’s most beautiful beaches (Figure 4) with the potential to attract significant foreign investment in international standard hotel and tourism. To take advantage of its natural resources, the government needs to regulate the shrimp industry in ways that take into account the loss and damage it causes. That will, over time, allow the turtles to return and contribute to more sustainable economic development.